A Surprise Lesson From Hurricane Dean

Recently, Hurricane Dean formed in the Atlantic, blew through the Lesser Antilles (Do they feel any inferiority with that name?), Jamaica, the Yucatan Peninsula and finally Mexico&#185.

Rightfully, Dean was classified a Category 5 hurricane. Top winds were reported as high as 160 mph. Dean was the first Category 5 storm to strike land as a Category 5 since Hurricane Andrew hit South Florida, 15 years ago.

The Global Warming chorus started up. “This is a sign of what’s to come,” was the message. “Look how much stronger these storms have gotten.” It’s a scary message.

Here’s the headline on a release I got a few days ago:

Yikes – Dean Gets Stronger

Earlier this evening, around 8:00 PM, The National Hurricane Center issued a statement saying Hurricane Dean had top winds of 155 mph.

DEAN IS AN EXTREMELY

DANGEROUS CATEGORY FOUR HURRICANE ON THE SAFFIR-SIMPSON SCALE.

SOME STRENGTHENING IS EXPECTED LATER TONIGHT…AND DEAN IS LIKELY

TO BECOME A CATEGORY FIVE HURRICANE PRIOR TO MAKING LANDFALL.

About a half hour later, based on recon data, Dean was upgraded to 160 mph.

000

WTNT64 KNHC 210034

TCUAT4

HURRICANE DEAN TROPICAL CYCLONE UPDATE

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007

835 PM AST MON AUG 20 2007

DATA FROM THE AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT CURRENTLY

INVESTIGATING HURRICANE DEAN INDICATE THAT MAXIMUM SUSTAINED WINDS

HAVE INCREASED TO 160 MPH…MAKING DEAN A POTENTIALLY CATASTROPHIC

CATEGORY FIVE HURRICANE ON THE SAFFIR-SIMPSON HURRICANE SCALE.

$$

FORECASTER KNABB

There’s really no practical difference between 155 mph and 160 mph. Wind force increases logarithmically with the wind speed. But there’s a great perception difference, because at 160 mph, Hurricane Dean becomes a Category 5 storm.

Should Dean strike the Yucatan Peninsula as a Cat 5, it will be the first Atlantic Basin Category 5 landfall since Andrew, 15 years ago!

The only good news is, Dean will be sufficiently south of Cancun to produce less damage than a direct hit. It’s still going to crush the region mercilessly.

Hurricane Dean – At The Antilles

Tonight, the Hurricane Center deemed Hurricane Dean’s winds to be sustained at 100 mph. Sure, why not?

I actually don’t think they’re blowing that fast. I’m basing my estimate on the look of the satellite imagery, surface observations and the Martinique radar.

The chain of islands Dean is approaching, the Antilles, will be quickly passed. Though Dean might damage them, they won’t slow Dean much at all. That seems unfair.

The next two days will probably see significant strengthening of this storm as it enters the Caribbean. On TV, meteorologists and others will point out Dean’s well defined and circular eye. We can’t do that quite yet.

The official pronouncement from the Hurricane Center calls for a period of Category 4 winds. There’s no certainty, but that seems a reasonable call. Dean is entering an area primed to be hurricane fuel.

Jamaica, the Caymans and the Yucatan Peninsula are all under attack if Hurricane Dean follows the computer guidance (amazingly in agreement with each other right now). All three areas are quite vulnerable.

After Katrina, some people were left with a false impression. There aren’t many places that can flood like New Orleans. Certainly none of the places I just mentioned floods that way.

The major damage from Dean will be related to strong, destructive winds. If you want the Katrina analogy, that’s the kind of damage produced on the Mississippi Coast.

A less sexy story, Mississippi a whole lot less news coverage than New Orleans. The damage was nonetheless catastrophic. Let’s hope I’m wrong.

It Could Ruin Your Day

It’s been pretty well established that an asteroid or comet, plunging into the area around the Yucatan Peninsula, was the cause of the demise of the dinosaurs. The ash and dust thrown up by this unfathomable event blotted out enough of the Sun’s energy to change our climate. The dinosaurs and much of the rest of Earth’s living creatures couldn’t evolve fast enough to survive.

In the 4.5 billion years of the Earth’s history, that’s not a terribly unusual event. Unfortunately, it was unusual to the dinosaurs and it would be jarring to us. Our time frame is very different than the Earth’s

I mention this because it’s amazing how close we come from time to time… today, for instance.

Monday, NASA scientists working on NEAT (Near Earth Asteroid Tracking) discovered a ‘small’ asteroid, which they named 2004FH. At 60-125 feet in diameter, it is tiny compared to the dinosaur’s nemesis. It’s still pretty darned big.

The 1908 Tunguska explosion, which leveled 750+ square miles of forest in Siberia, came from an asteroid not much larger!

NEAT is actually supposed to look for larger asteroids which might threaten the Earth (not that there’s anything we could do). 2004FH snuck in, despite its size, because of its proximity.

Tonight (March 18th at 5:08 PM EST) this asteroid will pass within 26,500 miles of Earth. Let’s try it another way. Scientists reference distances like this in AU, astronomical units, representing the average distance between Earth and Sun. 2004FH will be only .0003AU away!

If the distance to the Sun was one mile, this asteroid would be 1.5 feet away.

NASA says there’s no cause for alarm. It will pass safely by. Asteroids do all the time, though they’re seldom noticed before hand. This one won’t even be visible in North America.

Here’s how you’ll know if this bad boy really is trouble. If there’s no blog entry tomorrow – 2004FH was a little closer than anticipated..